A presumptive fentanyl test was positive, but investigators say private toxicology is still pending as the death investigation continues.
GOOSE CREEK, S.C. — The parents of a 13-year-old girl were arrested after their daughter was found dead at a Goose Creek-area home, with investigators later reporting a presumptive positive test for fentanyl while awaiting additional toxicology results.
Berkeley County sheriff’s deputies responded to a home on Keyes Lane on the morning of Aug. 27 after the girl’s mother tried to wake her for school and found that she was unresponsive, according to reports based on information from the Sheriff’s Office. Emergency medical personnel and firefighters responded and confirmed that the teenager had died. Authorities have not publicly identified the girl, and her death remains under investigation.
The girl’s parents, Tracy Lyn Castillo, 37, and Derrell Dominquez Joshua, 42, were at the home when authorities responded. Both were arrested by the Berkeley County Sheriff’s Office on Aug. 28, one day after their daughter was found dead. The arrests involved drug possession and child-neglect allegations, but authorities have not announced a homicide charge or said that either parent has been charged with causing the girl’s death.
Local reports citing Berkeley County records said Castillo and Joshua each face one count involving possession of more than two grains of fentanyl and three counts related to allegedly placing a child at risk, causing harm or neglecting a child while acting as a legal custodian. The precise wording used to describe the child-related counts has varied among published reports. The charges remain allegations and do not establish guilt.
The investigation took another step on Sept. 10, when officials said a test involving the girl produced a presumptive positive result for fentanyl. Authorities said they were still waiting for a private toxicology report. A presumptive result is preliminary, and investigators had not publicly announced a final toxicology determination or official cause and manner of death as of Monday.
That distinction is important because the available evidence has not yet established publicly that fentanyl caused the teenager’s death. Berkeley County’s overdose tracking system notes that suspected fatal overdoses are confirmed only after toxicology and autopsy findings are completed. Authorities have therefore continued to describe the girl’s death as an active investigation rather than announcing a final finding based solely on the initial test.
Investigators have released few details about what led to the fentanyl possession charges against Castillo and Joshua. Public reporting has not established where the suspected fentanyl was found, how authorities believe it came into the home or whether investigators have determined how the teenager may have been exposed to the drug. The Sheriff’s Office also has not publicly described evidence connecting either parent directly to the girl’s preliminary test result.
Local reporting also said multiple agencies assisted after deputies were called to the home. Authorities have not publicly released a detailed timeline of the hours before the girl was found unresponsive. No public account reviewed for this report identified another suspect or described evidence showing that the teenager knowingly took fentanyl. Those questions remain unresolved while investigators await additional testing.
The case comes as Berkeley County continues to track opioid-related emergencies. County coroner data for 2026 lists fentanyl among substances involved in local overdose cases, while also cautioning that overdose figures can change as reports and toxicology findings are completed. Those countywide figures do not determine what happened in this individual case, which must be established through its own medical and criminal investigation.
Published reports also indicate Castillo previously faced child-related charges in 2024. The available reporting does not establish the final outcome of those earlier allegations, and they do not prove the allegations in the current case. Joshua and Castillo are entitled to the presumption of innocence on the new charges unless they are proven guilty in court.
As of Sept. 14, the Berkeley County Sheriff’s Office had described the investigation as active and ongoing. The most significant unanswered issue is the final toxicology finding, which could clarify whether fentanyl played a role in the girl’s death. Authorities had not announced a final cause of death or additional charges tied directly to her death.
Author note: Last updated September 14, 2026.